원문정보
초록
영어
A recombinant β-galactosidase from Sulfolobus solfataricus produced galactooligosaccharides (GOS) from lactose by transgalactosylation. The enzyme activity for GOS production was maximal at pH 6.0 and 85°C. In thermal stability experiments, the half-lives of the enzyme at 70, 75, 80, 85, and 90°C were 700, 111, 72, 43, and 2.4 h, respectively. The optimal amount of enzyme for effective GOS production was 3.6 units ml-1 of enzyme. GOS production increased with increasing lactose concentration, whereas the yield of GOS from lactose was almost constant. Under the conditions of pH 6.0, 80°C, 600 g/L of lactose, and 3.6 units ml-1 of enzyme, GOS production was 310 g/L for 56 h, with a conversion yield of GOS from lactose of 52%. The final concentration of GOS and GOS yield from lactose used by β-galactosidases from S. solfataricus was the highest among thermostable β-galactosidases.